Preservation of fresh citrus fruits



Patented Apr. 11,1950 7 UNITED STATES PATENT OFFICE PRESERVATION OF FRESH CITRUS FRUITS Carl E. Gericke, Clewiston, Fla., asslgnor to American Machinery Corporation, Orlando, Fla., a corporation of Florida No Drawing. Original application August 23,

1946, Serial No. 692,701. Divided and this application April 25, 1949, Serial No. 89,559

3 Claims. (Cl. 99154) 1 2 This is a division of my co-pending application cules of the ionized surface active agent orient Serial No. 692,701, filed August 23, 1946. themselves so that the carbon chain of the mole- This invention relates to the commercial prepacules either dissolve in or are attracted by the ration of fresh whole fruit for the market wherefinely divided material to be emulsified or disin fungus control agents ar applied thereto. 5 persed, while the terminal groupings bearing the The essential object of the present invention charge of the molecules extend into the solvent. is the treatment of whole citrus fruit with an In this manner an aggregation of finely divided acid bath. and stabilized particles are formed in the solvent,

It is well known to use fungicides in an alkaline each of which are stabilized by one or more elecbath in rd r to reduce h p ilage of fruit af er tric charges. The surface active agents used in or during the treatment or D paraticn of the carrying out the present invention are of the fruit for the market and one of the well known cationic type which offer man advantages over fungicides is sodium benzoate. However in the the oth two types of surface active agents composition of the bath of the present invenpreviously ed,

@1011, 1888 fungicide-i. 8;, sodium benzoate, 80- 1.1 The anionic urface agents with respect to d um bcrate. Sodium yp r Calcium p structure are typified with respect to molecular chlorite and others commercially available-is configuration by long carbon h i l l required to preserve the fruit because of the acid Such as a fatty i hi h bears negative nature of the bat medium carrier than in charge when acting as an emulsifier or dispersing an alkaline bath of thepricr art, the bath of the m agent o t other hand t ti agents present invention enhancing the activity of the can be typified by a long carbon chain molecule fungicidal. agent toward the fruit- It is Z F with a terminal nitrogen containing group which fore Withm the contemplated Scope of thls i bears a positive charge when acting as a stabilizer vention to use approximately 6% of fungicide for an emulsion or suspensoi under the existing acid condition of the bath 2:, In carrying out the present invention an of the present invention where previously it has ganic amine salt Solution is mixed, with or with been necessafw to have 1% or m of the fungi" out heating (heating being used to accelerate present m the baths f the prior solution) with a fungicidal agent to form a conggi gfig gg iggzg sg g $32 33; gf i z u" centrate. This concentrate is further diluted and a surface active agent which has outstand to gl fe zr ggfi c r ir a l tz t g faii ing characteristics ashereinafter more specifically th f 1 th in set forth, but does not contemplate the use of a e are m e solvent as disclosed in the prior art, which solggifigg: 32:3 3 1 1 22; :{I amc 11;! invent removes the natural waxy coating from the g is g have one or more of fz fs igz m 1] fruit and is absorbed by and conta inates t e atoms attached to the nitrogen replaced y ypeel thereof.

t m the th' drocarbon radicals. It has been found that not It has been fmmd pm a1 p y all of the compounds falling within this class abov referred to, in the coloration of oranges as set forth in my co-pending application, 'above 40 Wm work Satlsfactonly, but 01115 those mentioned, and in which bath an oil-soluble Pounds wherein at least one Of h hydrocarbon water ins,oluble edible dye is incorporated; and group contains 10 to 18 carbon atoms. It should it has also e found practical in this bath com further be related that the secondary and tertiary taining the dye, to incorporate the fungicidal compounds should contain only one carbon chain agent of the present invention. However, it is i. of the'type just Specified d at the second side to be understood that the fungicidal agent alone 8 oupmg in the Secondary amine nd the secmay be incorporated in the bath of the present 0nd and third e ps n the tertiary am e invention t t th dye should contain as few carbon atoms as possible.

Certain surface active agents have several gen- The description herein given should not be coneral uses, one of which is a dispersion of a solid in strued to mean that ring configurations must be into a liquid to produce a suspensoid. These absent since it has been found that some comsurface active agents fall into three general pounds consisting of a long carbon chain moleclassifications, hydrophilic, anionic and cationic. cule to which is molecularly attached a nitrogen The cationic and anionic compounds are usually containing ring are also effective in the salt form long chain carbon compounds with a terminal as a'surface active agent.

grouping capable of ionizing when put into solu- The acids used are monoba ic acids such as tion in an aqueous solvent. when finely divided hydrochloric, hydrobromic, acetic, formic, lactic, material, which is to be emulsified or dispersed, etc. It is well known that many commercial is placed or produced in such a solvent containamines on the market are handled under trade in: an ionized surface active agent, the molenames and are sometimes a mixture of amines asoaees rather than a pure compound. These mixtures sirable if equivalent fungicidal protection could are satisfactory. The Sharples Chemical Commay and Amour 8; Company are two corporations marketing such amines.

The following compounds have been tried:

be obtained which is the case with the present invention. Practically all of the materials now used for fungicidal Purposes are more active in an acid medium and therefore much less of the Trade name or designation bu Armour a: Company as o! 1945 Chain Length AM-ll20 Amines, present-primary AMI-1140 AM1160 AM-ll8.5-B AM-iiso AM-Coco-B Per cent Per cent Per cent Per cent Per cent Ave. M01. Wt

amine by titration Approx. melting point, C

285 s as.

ssfi ass cs ass as sea 53 mmmasom All were of the "purified" grade (distilled).

Any one of the above amines or any mixture thereof may be employed. In addition to those compounds in the above table, the compounds known as AM-2120 and AMCL-4 Coco-C may be employed, the first compound consisting primarily of didodecyl ammonium chloride (secondary amine) and the second compound consisting of a mixture of quaternary ammonium salts containing an aliphatic side chain having 12 to 14 carbon atoms. The best results were obtained with AMCL-4 Coco-C and AMCoco-B and AM-2120.

As one example or formula for practicing the invention, mix the desired amount of the fungicidal agent (as above mentioned) and 18 pounds of AM-Coco-B and heat, preferably with stirring, the necessary amount of hydrochloric or acetic acid being added to neutralize the amine; and, preferably, when the amine or AM-Coco-B has melted (if previously in a solid state) sufficiently to be incorporated with the other ingredients of the mixture, water is added to about 20 gallons to form a concentrate. This concentrate is further diluted to make a bath by adding it to parts of water for each part of concentrate. The fruit is contacted by floating and submerging them in said bath. The temperature of the bath may be as much as between 104 F. to 118 F. for a period of 4 /2 minutes. It is to be noted that the temperature employed is well below the legal maximum of 127 F. allowed by law for treatment of citrus fruit. The temperature of the bath may be reduced from that stated, provided the oranges remain therein for a longer period of time. The bath is acid in reaction as it contains the salt made by the combination of a weak base and a strong acid.

The other amine compounds, mentioned above, may be mixed and prepared with the fungicidal agent and water in substantially the same manner and proportions asstated in the example or formula just given. This formula may be further enhanced by the addition of a small amount of alpha terpineol as an anti-foaming agent, bu thi is not necessary.

It is well recognized that the smallest possible amount of fungicidal substances is highly desirable as they are not beneficial to the human system. Certain laws have been passed limiting the use to less than a given percentage of preservative materials. It is, therefore, easily seen.

that a lower percentage of sodium benzoate or other fungicidal material would be highly defungicidal agent is necessary to produce the desired result.

Among the advantages of this bath and process over existing baths and processes is the fact that water containing iron or other dissolved mineral matter, such as hard water as is found in those communities where limestone or coral formations are common, may be used directly without a preliminary treatment. This is possible because the bath is acid in reaction and not alkaline as is used today. Therefore, the alkaline earth and metallic elements remain in solution rather than precipitate out as soaps. These would foul the bath and render it inoperative.

Having thus fully described my invention and set forth as well as possible the composition of the compound purchased under trade names so as to enable others skilled in the art to use and compound the same, I claim as my invention and desire to secure by Letters Patent the following:

1. A bath for the treatment of citrus fruit containing a fungicidal agent and a substituted ammonium salt having at least one hydrocarbon chain of 10 to 18 carbon atoms.

2. In a process for the prevention of mold growth in citrus fruit, the step of bringing the fruit into contact with a fungicidal agent in an acid bath containing the salt of amine having at least one hydrocarbon side chain of 10 to 18 carbon atoms.

3. In a process for the prevention of mould growth in citrus fruit, the step of bringing the fruit in contact with a bath containing a fungicidal agent and an aliphatic substituted amine salt of a strong acid, said amine having at least one hydrocarbon side chain of 10 to 18 carbon atoms, and said bath having an acid reaction by virtue of the salt contained therein.

CARL- E. GERICKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

1. A BATH FOR TREATMENT OF CITRUS FRUIT CONTAINING A FUNGICIDAL AGENT AND A SUBSTITUTED AMMONIUM SALT HAVING AT LEAST ONE HYDROCARBON CHAIN OF 10 TO 18 CARBON ATOMS. 